Driving comfort depends on a multitude of factors, such as vehicle suspension, tire properties, road conditions etc. A relevant factor is whether the vehicle is driven along a smooth road surface or into potholes and across bumps. With potholes is here understood disruptions in the road surface where a portion of the road material has broken away, leaving a hole. With bumps is here understood disruptions in the road surface where a portion of the road is raised, forming an upwardly extending protrusion. If contact with bumps and potholes can be avoided, a perceived driving comfort may be increased.
Presently, the use of vehicles comprising alternate propulsion sources such as electric motors is on the rise. Vehicles may be either pure electric vehicles (EV), hybrid electric vehicles (HEV) or plug-in hybrid electric vehicle (PHEV). The HEV and the PHEV uses more than one power source, i.e. both an internal combustion engine and an electric motor. Environmental and economic concerns have given rise to optimization of the usage of the different propulsion sources in order to reach a more efficient fuel consumption and to reduce emissions from the vehicle.
One example of such an optimization can be found US 2011/0246004. Here the optimization is based on calculating a route which uses the least amount of energy. The calculation is made from energy maps where the energy usage for one or more propulsion source is mapped. Using a start and end point the optimization sends a suitable route to the vehicle.
One problem with the above optimization is that the optimization relies on data collection from probe vehicles which is expensive and time consuming. Further, different probe vehicles have to be used in order to collect data for different vehicle types. Another is that by using energy usage as a means of optimizing the route certain parameters, such as state of charge, may go unused leading to a less efficient optimization.
There is thus a need for an improved optimization method for vehicles.